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Htmlq: like jq, but for html

github.com

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Re: Htmlq: like jq, but for html

#81

Post by zimpenfish »

samhw wrote: post #63
chriswarbo wrote: post #37

Earlier quoted context omitted.

Thanks, that's a rare example of something which is (a) simple enough to understand for a Prolog-newbie like me, and (b) more practical than ubiquitous family-tree example. I'm always looking for opportunities to dip my toes into Prolog; in hindsight it's clearly a good fit for tree-structured data structures.

Interestingly, the only other context in which I've come across Prolog is from friends who studied at Cambridge, here in the UK. For some reason, the CS 'tripos' (course) there is really heavily focussed on Prolog, and everyone I know from there ended up a huge fan of the language. I'm not sure why that's the case, though, given that almost all other universities seem to use more common languages (Java, C++, etc).

cs.man.ac.uk, at least back in 1992, had a compulsory Prolog module in the first year. Don't know anyone from then who didn't hate that module with a burning passion.

(There was no Java, C++, etc. either. It was SML, Pascal, 68000, and Oracle Pascal-Embedded-SQL.)

Re: Htmlq: like jq, but for html

#82

Post by zamadatix »

srg0 wrote: post #75

"htmlq: like jq, but for HTML" "jq is like sed for JSON data" sed: "While in some ways similar to an editor which permits scripted edits (_such as ed_), sed works by making only one pass over the input(s)" ed: "ed is a line-oriented text editor". Software definition through a reference to another software is somewhat confusing. Potential users come from different backgrounds (I had no idea what is jq), and it is not…

1st sentence - Explaining the tool for those the tool was made for without beating around the bush.

2nd sentence - Explaining the tool to folks in the general web domain what it can do for them.

3rd sentence - Explaining where to learn how to use the tool if you've stumbled across it but web is not your area of expertise.

All that info fits in nearly 25 words then it lists the options for the tool and jumps straight into multiple examples (with outputs!). If the only explanation had been "htmlq: like jq, but for HTML" I'd agree but having the comparison to explain what it does isn't a bad thing it's _only_ having the comparison that would be bad.

Personally I think this is a model example of a opening for a Github readme.

Re: Htmlq: like jq, but for html

#83

Post by pandatigox »

triska wrote: post #31

This is very nice! For reasoning about tree-based data such as HTML, I also highly recommend the declarative programming language Prolog. HTML documents map naturally to Prolog terms and can be readily reasoned about with built-in language mechanisms. For instance, here is the sample query from the htmlq README, fetching all elements with id get-help from https://www.rust-lang.org , using Scryer Prolog and its SGML a…

I tried to run this on my computer now, but as a complete Prolog noob, I'm having errors running the script? How do you load the http_open module/library in the first place? I tried following some Prolog tutorials in the past but I always get stuck trying to run something in the REPL. I'm using scryer-prolog. Thanks in advance!

Re: Htmlq: like jq, but for html

#84

Post by theandrewbailey »

oauea wrote: post #78
srg0 wrote: post #75

"htmlq: like jq, but for HTML" "jq is like sed for JSON data" sed: "While in some ways similar to an editor which permits scripted edits (_such as ed_), sed works by making only one pass over the input(s)" ed: "ed is a line-oriented text editor". Software definition through a reference to another software is somewhat confusing. Potential users come from different backgrounds (I had no idea what is jq), and it is not…

What's this thing called a "computer" that people keep going on about, anyway?

It's like a programmable loom, but for logical and mathematical operations.

Re: Htmlq: like jq, but for html

#85

Post by parhamn »

Ive been looking for a library that can find the best set of selectors to most consistently find the element youre looking for in a page.

Any pointers to something that exists? Interestingly I've also found very little for dom extraction in the OS ML space.

Re: Htmlq: like jq, but for html

#86

Post by throwaway2016a »

srg0 wrote: post #75

"htmlq: like jq, but for HTML" "jq is like sed for JSON data" sed: "While in some ways similar to an editor which permits scripted edits (_such as ed_), sed works by making only one pass over the input(s)" ed: "ed is a line-oriented text editor". Software definition through a reference to another software is somewhat confusing. Potential users come from different backgrounds (I had no idea what is jq), and it is not…

I agree, however if you do know how to use jq than "like jq, but for html" is extremely effective. I use jq all the time and that title hooked me, I immediately wanted to try it.

But if you haven't used Jq that I can see how that title is less than helpful.

Re: Htmlq: like jq, but for html

#87

Post by corporealshift »

srg0 wrote: post #75

"htmlq: like jq, but for HTML" "jq is like sed for JSON data" sed: "While in some ways similar to an editor which permits scripted edits (_such as ed_), sed works by making only one pass over the input(s)" ed: "ed is a line-oriented text editor". Software definition through a reference to another software is somewhat confusing. Potential users come from different backgrounds (I had no idea what is jq), and it is not…

I mean...if you read the github readme it literally describes what it does in the next line: "Uses CSS selectors to extract bits content from HTML files".

Re: Htmlq: like jq, but for html

#88

Post by zamadatix »

d--b wrote: post #79

Just being that guy: is there a reason you didn't call it hq?

Not author but neither is the poster: Jq got away with it because it's one of the few 2 letter combinations that wasn't absolutely overloaded and "jquery" was already taken. OTOH nobody shortens HTML to H and HQ is an extremely common acronym, if not one of the most popular 2 letter acronyms you could pick.

Re: Htmlq: like jq, but for html

#90

Post by desktopninja »

Very nice tool. I've long spoiled myself with Powershell's:

  Invoke-WebRequest

  eg. # what is the latest release of apache-tomcat?
  $LINKS=$(Invoke-WebRequest -Uri 'https://tomcat.apache.org/download-80.cgi' | Select-Object -ExpandProperty Links)
  $LATEST=$($Links | Where-Object -Property href -Match '#8.5.[0-9]+').href.substring(1)
  $FETCH=$($Links | Where-Object -Property href -match "apache-tomcat-${LATEST}.zip$").href
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